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Showing items 1 through 9 of 6.
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Library Resource
Severe soil erosion and food security problems are the most important issues in the Loess Plateau of northern China, which are closely related to the over-cultivation and poor management of marginal land resources. Alleviation of these unsustainability problems requires, among many other things, alternative and innovative cropping systems. This paper describes the identification of such cropping systems and their quantitative evaluation.
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Library Resource
It is well recognized that aggregation of the inhomogeneous data for soils, management, and weather within a land unit for crop simulation plays a key role in the scaling-up task of crop simulation at regional scales. While the other spatial data could be obtained at a desired level, weather data might not be available in mountainous regions where the production system is comprised of many small farms.
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Library Resource
Degradation of the dry semiarid ecosystems in the Mu Us Sandy Land of north central China was explored using high-resolution satellite images from 1978, 1987 and 1996. This study monitored both changes in grassland biomass production and reclamation activities to detect the nature and scale of land degradation since major economic reforms were introduced in 1978. The position of the high-resolution images within the vegetation cycles was inspected from National Oceanographic and Atmospheric Administration (NOAA) NDVI images at 10-day repetition and seasonal precipitation patterns.
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Library Resource
Honduras, Grèce, Haïti, Japon
World population is increasing, particularly in the developing countries. Groundwater reserves are being depleted; lands are being degraded. The required increase in food production must come principally from new supplies of water for irrigated lands. If irrigated lands fail to produce the required food, increased destruction of resources and degradation of the environment from increasing slash and burn agriculture is anticipated. Various countries and international agencies have recognized the possibility of future food shortage.
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